It happens. Joshua has been taking on top 5 opponents and he's not THAT far ahead of them. Most heavyweight champs fight a couple of cannon fodder dudes between tough fights. If Joshua did that he'd still look spectacular.
Happens to a lot of fighters, they look brilliant on the way up but when they get to that top level it all becomes that little but harder, would be very surprised if Joshua had kept KOing people like Wlad, Takam, Parker as easily as Johnson, Molina etc. I expected Takam to take him late and Parker to take him the distance, too many seem to forget there are levels too this game, they see him KOing mediocre fighters and expect the same when he's up against tougher opposition which is simply unrealistic.
Which is needed sometimes, people get on these hype trains and lose all perspective and expect their latest favourite fighter to destroy everyone in 3 rounds and then they have a small nervous breakdown when they don't lol.
Parker with that cringeworthy presser they streamed online really made a fool out of himself. He did "okay" in the fight without trying to win. He really should shut up now about AJ; Parker lost fair and square and didn't behave very manly before nor after the fight.
Wilder doesn't want that. He will avoid fighting boxers like Parker, Whyte, Povetkin and Joshua until he decides to cash out or eventually ends up losing to a semi-good fighter as he has been close to a few times already.